My orginal problem in one sentance: "When I use nslookup with a simple
hostname, DNS fails and is actually looking for 'hostname.co.uk'."

Hitting the nail on the head, Doug Bloebaum <blabes@datalytics.com>, was
kind enough to at work on time in EST, and hence mailed back thusly:-

> I got bit by this one a while back, too. It seems that Sun's resolver
> will append the NIS (and I assume NIS+) domainname to DNS queries.
> This makes sense. The part that doesn't is that it strips the first
> level from the domainname UNLESS it begins with a "+". To get around
> this I added the following line to /etc/resolv.conf:
>
> domain saa-cons.co.uk